1. Field of the Invention
The present invention relates to a semiconductor optical element used as a light source for optical fiber communication or optical disk recording and a method of manufacturing the same.
2. Background Art
A semiconductor laser having quantum dots formed in its active layer (see, for example, IEEE JOURNAL SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 11, No. 5, SEPTEMBER/OCTOBER 2005, pp 1027-1034) and a waveguide-type light receiving element having quantum dots formed in its absorption layer (see, for example, IEEE JOURNAL OF QUANTUM ELECTRONICS, VOL. 35, No. 6, JUNE 1999, pp 936-943) has been proposed. A semiconductor laser in which the density of quantum dots in its active layer is varied in a plane perpendicular to the resonator direction (light travel direction) has also been proposed (see, for example, Japanese Patent Laid-Open No. 11-307860).